The coroner's office released its report Thursday afternoon, calling the 48-year-old's death accidental. Houston was found dead by a member of her entourage on Feb. 11 in a bathtub at the Beverly Hilton Hotel.

"It appeared that the cocaine had been used in the time period just probably immediately prior to her collapse in the bath tub at the hotel," Coroner's Chief of Operations Craig Harvey said.

Harvey said the singer suffered a "cardiac event."

"A 60 percent artery narrowing resulted in the finding of a heart condition. That condition, combined with chronic cocaine use, exacerbated the fact that she died of accidental drowning," Harvey said.

In addition to cocaine and metabolites found in the singer's system, the coroner also identified traces of marijuana, Xanax (anti-anxiety), Flexeril (muscle relaxant) and Benadryl (antihistamine), although they did not contribute to her death, according to the report.

"We are saddened to learn of the toxicology results, although we are glad to now have closure," said Houston's sister-in-law and manager, Patricia Houston.

After the singer's death, investigators issued subpoenas for records of her medical prescriptions, apparently pursuing the possibility that prescription abuse was a factor in her sudden death.

Prescription bottles were found in Houston's room at the Beverly Hilton hotel, investigators said. However, after weeks of rigorous lab work, the coroner's report indicates that prescription drugs do not appear to have played a significant role in the singer's death.

Remembering Whitney Houston

On the day of her death, Houston had planned on attending Clive Davis' annual pre-Grammy party. Her daughter, Bobbi Kristina, was at the hotel at the time of Houston's death.